Schoch, Bradley S.

Aims Reverse shoulder arthroplasty (RSA) after prior rotator cuff repair (RCR) is commonly performed for recurrence of pain and arthritic progression; however, the influence of prior RCR timing and technique on outcomes of RSA has not been adequately explored. Our primary aim was to evaluate the relationship between the postoperative American Shoulder and Elbow Surgeons (ASES) score, whether prior RCR was performed open or arthroscopic, and the time interval between RSA and prior RCR. Secondary outcomes were forward elevation (FE) and external rotation (ER). Methods A prospectively collected single-institution shoulder arthroplasty database was queried to identify patients undergoing primary RSA after prior RCR between 2004 and 2022 for non-tumour and non-fracture indications with minimum two-year follow-up. We evaluated the relationship between the postoperative ASES score, FE, and ER stratified by prior RCR approach (open vs arthroscopic) and time between RSA and RCR. Multivariable analysis was used to adjust for potential confounders. Results We included 104 RSAs (99 patients) with a mean 8.8 years (SD 7.3) after RCR and a mean age of 68 years (SD 8.3). Prior RCR was performed arthroscopically in 40 RSAs (38%). Mean follow-up was 4.8 years (SD 2.8). On multivariable analysis, arthroscopic RCR was independently associated with a 13-point greater postoperative ASES score (p = 0.008), 14° greater forward elevation (p = 0.011), and 8° greater external rotation (p = 0.018) compared with open RCR. A ten-year increase in time between RCR and RSA was associated with a seven-point greater postoperative ASES score (p = 0.029) and 5° greater external rotation (p = 0.015). Conclusion A greater time interval between prior RCR and RSA, as well as arthroscopic techniques, is associated with improved outcomes after primary RSA in patients with prior RCR. Cite this article: Bone Joint J 2026;108-B(7):928–935.

Background/Objectives: Non-typhoidal Salmonella (NTS) species are well-recognized causes of invasive infection in patients with sickle cell disease (SCD), with a particular predilection for the musculoskeletal system. Although Salmonella osteomyelitis is well described in this population, septic arthritis is uncommon, especially involving the shoulder joint. We describe a case of NTS bacteremia complicated by native shoulder septic arthritis in a patient with SCD and review its clinical implications. Methods: We report the clinical course, diagnostic evaluation, microbiologic findings, imaging studies, and management of a 22-year-old man with homozygous SCD who presented with a vaso-occlusive pain crisis and subsequently developed severe sepsis with persistent Salmonella enterica bacteremia following ingestion of undercooked poultry. Persistent bacteremia prompted further evaluation for metastatic infection using advanced imaging and diagnostic arthrocentesis. Results: Whole-body imaging identified septic arthritis of the native right shoulder, which was confirmed by synovial fluid cultures growing Salmonella species. The patient underwent arthroscopic irrigation and debridement for source control. Antimicrobial therapy was narrowed to intravenous ceftriaxone based on susceptibility data and continued for six weeks. The patient demonstrated clinical improvement with resolution of bacteremia and was discharged to rehabilitation to complete therapy. Conclusions: This case highlights the importance of a careful exposure history, including foodborne sources, in patients with SCD presenting with invasive Salmonella infection. Persistent bacteremia should prompt early investigation for metastatic foci, and timely surgical source control combined with targeted antimicrobial therapy is essential for optimal outcomes in this population.

ABSTRACT The goal of this radiomic analysis is to quantify the sensitivity of radiomic features on computed tomography (CT) image pre‐processing parameters and use machine learning (ML) techniques to identify the radiomic features that are highly predictive of shoulder arthroplasty outcomes. An ML framework auto‐segmented 3D masks of the deltoid muscle and scapula bone from pre‐operative CT images of 1949 primary anatomic total shoulder arthroplasty (aTSA)/reverse total shoulder arthroplasty (rTSA) patients. Radiomic features were extracted after various image pre‐processing protocols and assessed for reproducibility. The radiomic features deemed robust to image pre‐processing were used to train ML predictive outcomes models. Feature importance data were rank‐ordered to identify the radiomic features that were highly predictive of pain, motion, and function before and after aTSA/rTSA. A sensitivity analysis identified 37 deltoid muscle and 38 scapular bone radiomic features that were robust, reproducible, and unique across image pre‐processing parameters. The most predictive deltoid muscle radiomic measurements were normalized volume, elongation, flatness, fat percentage, sphericity, and max 2D diameter column. The most predictive scapular bone radiomic measurements were flatness, sphericity, elongation, max 2D diameter column, and max 2D diameter slice. Radiomic data of the deltoid and scapula were highly predictive of pain, motion, and function before and after aTSA and rTSA. Radiomic data were more predictive than patient comorbidities, diagnosis, and implant type/size data, but less predictive than pre‐operative active range of motion measurements and patient reported outcome measures, 3D measurements from planning software, or patient demographic data. Future work is required to clinically validate these radiomic features before they can be deployed in clinical decision support tools. Level of Evidence Level III, Retrospective Comparative Outcome Study.

While anatomic total shoulder arthroplasty is a successful procedure that provides reliable pain relief and restoration of function in most patients, its success has been limited by glenoid component loosening. While series reporting the outcomes of inlay glenoid components have demonstrated excellent clinical outcomes with low rates of component loosening and need for revision, surgeons have been hesitant to adopt these implants due to concerns of inadequate pain relief secondary to the remaining glenoid rim contacting the humeral head implant. The inset glenoid component, a variant of the traditional inlay components, has gained interest because its design aims to achieve similar stability to traditional inlay components through implantation within strong subchondral bone, reduce the amount of glenoid vault removed compared to inlay components, and has a glenoid face designed to limit the rocking-horse phenomenon. In limited series, the inset glenoid component has demonstrated superior biomechanical and clinical performance compared to traditional onlay glenoid components. Although there have been minimal clinical studies investigating the inset glenoid in comparison to onlay and inlay components to date, a subset of case series with short-term follow-up have demonstrated favorable outcomes. The purpose of this article was to review the design rationale, biomechanical evidence, and clinical performance of the inset glenoid component.

Introduction: We developed a computed tomography (CT)-based tool designed for automated segmentation of deltoid muscles, enabling quantification of radiomic features and muscle fatty infiltration. Prior to use in a clinical setting, this machine learning (ML)-based segmentation algorithm requires rigorous validation. The aim of this study is to conduct shoulder expert validation of a novel deltoid ML auto-segmentation and quantification tool. Materials and Methods: A SwinUnetR-based ML model trained on labeled CT scans is validated by three expert shoulder surgeons for 32 unique patients. The validation evaluates the quality of the auto-segmented deltoid images. Specifically, each of the three surgeons reviewed the auto-segmented masks relative to CT images, rated masks for clinical acceptance, and performed a correction on the ML-generated deltoid mask if the ML mask did not completely contain the full deltoid muscle, or if the ML mask included any tissue other than the deltoid. Non-inferiority of the ML model was assessed by comparing ML-generated to surgeon-corrected deltoid masks versus the inter-surgeon variation in metrics, such as volume and fatty infiltration. Results: The results of our expert shoulder surgeon validation demonstrates that 97% of ML-generated deltoid masks were clinically acceptable. Only two of the ML-generated deltoid masks required major corrections and only one was deemed clinically unacceptable. These corrections had little impact on the deltoid measurements, as the median error in the volume and fatty infiltration measurements was <1% between the ML-generated deltoid masks and the surgeon-corrected deltoid masks. The non-inferiority analysis demonstrates no significant difference between the ML-generated to surgeon-corrected masks relative to inter-surgeon variations. Conclusions: Shoulder expert validation of this CT image analysis tool demonstrates clinically acceptable performance for deltoid auto-segmentation, with no significant differences observed between deltoid image-based measurements derived from the ML generated masks and those corrected by surgeons. These findings suggest that this CT image analysis tool has potential to reliably quantify deltoid muscle size, shape, and quality. Incorporating these CT image-based measurements into the pre-operative planning process may facilitate more personalized treatment decision making, and help orthopedic surgeons make more evidence-based clinical decisions.

Background: When missing data are present in clinical outcomes studies, complete-case analysis (CCA) is often performed, whereby patients with missing data are excluded. While simple, CCA analysis may impart selection bias and reduce statistical power, leading to erroneous statistical results in some cases. However, there exist more rigorous statistical approaches, such as single and multiple imputation, which approximate the associations that would have been present in a full dataset and preserve the study’s power. The purpose of this study is to evaluate how statistical results differ when performed after CCA analysis versus imputation methods. Methods: This simulation study analyzed a sample dataset consisting of 2204 shoulders, with complete datapoints from a larger multicenter total shoulder arthroplasty database. From the sampled dataset of demographics, surgical characteristics, and clinical outcomes, we created five test datasets, ranging from 100 to 2000 shoulders, and simulated 10–50% missingness in the postoperative American Shoulder and Elbow Surgeons (ASES) score and range of motion in four planes in missing completely at random (MCAR), missing at random (MAR), and not missing at random (NMAR) patterns. Missingness in outcomes was remedied using CCA, three single imputation techniques, and two multiple imputation techniques. The imputation performance was evaluated relative to the native complete dataset using the root mean squared error (RMSE) and the mean absolute percentage error (MAPE). We also compared the mean and standard deviation (SD) of the postoperative ASES score and the results of multivariable linear and logistic regression to understand the effects of imputation on the study results. Results: The average overall RMSE and MAPE were similar for MCAR (22.6 and 27.2%) and MAR (19.2 and 17.7%) missingness patterns, but were substantially poorer for NMAR (37.5 and 79.2%); the sample size and the percentage of data missingness minimally affected RMSE and MAPE. Aggregated mean postoperative ASES scores were within 5% of the true value when missing data were remedied with CCA, and all candidate imputation methods for nearly all ranges of sample size and data missingness when data were MCAR or MAR, but not when data were NMAR. When data were MAR, CCA resulted in overestimates of the SD. When data were MCAR or MAR, the accuracy of the regression estimate (β or OR) and its corresponding 95% CI varied substantially based on the sample size and proportion of missing data for multivariable linear regression, but not logistic regression. When data were MAR, the width of the 95% CI was up to 300% larger when CCA was used, whereas most imputation methods maintained the width of the 95% CI within 50% of the true value. Single imputation with k-nearest neighbor (kNN) method and multiple imputation with predictive mean matching (MICE-PMM) best-reproduced point estimates and intervariable relationships resembling the native dataset. Availability of correlated outcome scores improved the RMSE, MAPE, accuracy of the mean postoperative ASES score, and multivariable linear regression model estimates. Conclusions: Complete-case analysis can introduce selection bias when data are MAR, and it results in loss of statistical power, resulting in loss of precision (i.e., expansion of the 95% CI) and predisposition to false-negative findings. Our data demonstrate that imputation can reliably reproduce missing clinical data and generate accurate population estimates that closely resemble results derived from native primary shoulder arthroplasty datasets (i.e., prior to simulated data missingness). Further study of the use of imputation in clinical database research is critical, as the use of CCA may lead to different conclusions in comparison to more rigorous imputation approaches.

Background: Reverse shoulder arthroplasty (RSA) is increasingly used in the treatment of proximal humerus fractures (PHFs) with reliable clinical improvement. Lateralized RSA implants have conferred superior outcomes compared with the original Grammont design in patients with nontraumatic indications. However, in the setting of a PHF, lateralized components can place increased tension across the tuberosity fracture site and potentially compromise tuberosity healing and outcomes. This systematic review and meta-analysis sought to determine the effect of implant design on clinical outcomes after RSA for PHFs. Methods: A systematic review was performed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane were queried for clinical studies on RSA performed for PHFs that reported implant manufacturer details. Our primary outcomes included postoperative external rotation (ER), forward elevation (FE), abduction, Constant score, rate of greater tuberosity (GT) healing, and the incidence of complications compared between medialized vs. lateralized global implant design. Results: Globally lateralized RSA cohorts (478 RSAs total with cumulative lateral offset achieved through humeral or glenoid lateralization or both humeral and glenoid lateralization) were found to have a greater mean postoperative Constant score compared with globally medialized (medialized glenoid and medialized humerus) RSA cohorts with 1,494 total medialized RSAs (66 vs. 59, p = 0.006), but there was no significant difference regarding mean postoperative ER (30° vs. 22°, p = 0.078), FE (117° vs. 119°, p = 0.708), or abduction (103° vs. 107°, p = 0.377). On meta-regression, neither implant design nor tuberosity status significantly influenced postoperative ER, FE, abduction, or Constant score on meta-regression independent of mean follow-up and age at surgery. The rate of GT healing was greater in lateralized compared with medialized RSAs (88% vs. 72%, p < 0.001). On meta-regression, medialized RSA design was associated with a 73% lower odds of GT healing (odds ratio = 0.27, 95% confidence interval = 0.11-0.68, p = 0.007) independent of mean follow-up and age at surgery. Conclusion: Lateralized RSA implants conferred no significant functional benefit over medialized implants when used in patients with PHFs. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Background A variety of clinically important benchmarks of success (CIBS) have been defined for total shoulder arthroplasty (TSA) to quantify success. However, it is unclear how the preoperative status of the patient influences their likelihood of achieving each CIBS. Questions/purposes (1) What proportion of patients achieve commonly used CIBS after TSA? (2) Is there a relationship between a patients’ preoperative function and their probability of achieving different CIBS? (3) Does there exist preoperative ranges for each outcome measure that are associated with greater achievement of CIBS? Methods We retrospectively queried a multicenter shoulder arthroplasty database for primary anatomic TSA (aTSA) and reverse TSA (rTSA). A total of 2041 aTSAs and 3205 rTSAs were included. The mean ± SD age at time of surgery was 66 ± 9 years for aTSAs and 72 ± 8 years for rTSAs. In all, 51% (1049 of 2041) of aTSAs and 61% (1955 of 3205) of rTSAs were in patients who were women. For aTSAs, osteoarthritis with an intact rotator cuff was the most common preoperative diagnosis (92% [1869 of 2041]). For rTSAs, the most common preoperative diagnoses included rotator cuff tear arthropathy (40% [1280 of 3205]), osteoarthritis with an intact rotator cuff (24% [780 of 3205]), osteoarthritis with a torn rotator cuff (20% [632 of 3205]), and massive rotator cuff tear (10% [309 of 3205]). Outcomes were evaluated at latest follow-up (aTSA 61 ± 36 months, rTSA 47 ± 26 months) and consisted of ROM (abduction, forward elevation, external and internal rotation) as well as the most commonly used outcome scores: the Simple Shoulder Test (SST), Constant score, American Shoulder and Elbow Surgeons (ASES) score, University of California, Los Angeles (UCLA) score, Shoulder Pain and Disability Index (SPADI), and the Shoulder Arthroplasty Smart (SAS) score. The CIBS that we evaluated included the minimum clinically important difference (MCID), substantial clinical benefit (SCB), patient acceptable symptom state (PASS), minimum clinically important percentage of maximal possible improvement (MCI-%MPI), and substantial clinically important percentage of maximal possible improvement (SCI-%MPI). Prosthesis-specific anchor-based CIBS were adopted from prior publications on patients from this database. Multivariable regression was performed to identify the relationship between preoperative outcome measures and achievement of CIBS. Additionally, receiver operating characteristic (ROC) curve analyses were performed to determine whether thresholds in preoperative outcome measures were associated with achieving CIBS. Results For all ROM measures and outcome scores, poorer preoperative ROM was associated with greater odds of achieving the MCID and SCB but lower odds of achieving the PASS. For the SST and the two scores without ceiling effects (the Constant and SAS scores), poorer preoperative outcome scores were associated with greater odds of achieving the MCI-%MPI and SCI-%MPI, but no association was demonstrated for the ASES, SPADI, and UCLA scores. Graphical analysis demonstrated that patients with greater preoperative ROM and outcome scores had a lower probability of achieving the MCID and SCB but a higher probability of achieving the PASS. For outcome scores with known ceiling effects, patients with more favorable preoperative outcome scores were more likely to achieve the MCI-%MPI and SCI-%MPI than the MCID and SCB, respectively. For outcome scores without ceiling effects, patients undergoing aTSA were more likely to achieve the MCID, MCI-%MPI, and the SCI-%MPI than the SCB, but no clear trend was identified for patients undergoing rTSA. On ROC curve analysis, identified thresholds were reasonably accurate (area under the curve > 0.7) for achievement of measures of absolute improvement (the MCID and SCB), but not for absolute postoperative status (the PASS) or relative improvement (the MCI-%MPI and SCI-%MPI). Conclusion While most patients reported being “much better” (aTSA 75%, rTSA 76%) or “better” (aTSA 15%, rTSA 18%) compared with before surgery, 10% of aTSAs and 6% of rTSAs were either “unchanged” or “worse.” Patients’ likelihood of achieving CIBS depends in part on their baseline function and whether success is defined as absolute improvement, absolute postoperative status, or relative improvement. Patients with more favorable preoperative status are more likely to achieve CIBS that evaluate relative improvement (the MCI-%MPI and SCI-%MPI) than absolute improvement (the MCID and SCB). Future studies are needed to determine which individual CIBS or combinations thereof most accurately represent clinically relevant benefit. Level of Evidence Level III, therapeutic study.

Background: Reverse shoulder arthroplasty (RSA) is increasingly used in the treatment of displaced proximal humerus fractures (PHFs) with reliable clinical improvement. However, the preferred techniques for humeral stem fixation are varied and may be influenced by patient and injury characteristics, including bone quality and fracture pattern. This systematic review and meta-analysis sought to determine the effect of humeral component cementing and bone grafting on tuberosity healing rates and functional outcomes after RSA for PHFs. Methods: A systematic review was performed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane were queried for clinical studies on RSA performed for PHFs that reported on the use of cemented humeral stems and autograft bone. The primary outcome was the rate of greater tuberosity healing between the various techniques. Secondarily, the authors compared clinical outcomes including postoperative external rotation, forward elevation, abduction, Constant score, and the incidence of complications and revision surgery. Outcomes were compared based on the use of an uncemented press-fit stem, a fully cemented stem without bone graft, or a partially cemented stem with humeral head autograft (i.e., black and tan technique). Results: Forty-eight studies reporting on 1,797 RSAs were included (mean patient age, 75 years; follow-up, 34 months; 81% female). Tuberosity healing was highest in the uncemented cohort, then the black and tan cohort, and lowest in the cemented cohort (80% vs. 70% vs. 61%, p = 0.006). No significant differences in postoperative range of motion, Constant score, complication rates, or revision rates were found. Conclusion: Uncemented fixation with a press-fit stem was associated with superior greater tuberosity healing rates; however, functional outcomes and complications did not differ among techniques. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

AimsWe sought to compare functional outcomes and survival between non-smokers, former smokers, and current smokers who underwent anatomical total shoulder arthroplasty (aTSA) in a large cohort of patients.MethodsA retrospective review of a prospectively collected shoulder arthroplasty database was performed between August 1991 and September 2020 to identify patients who underwent primary aTSA. Patients were excluded for preoperative diagnoses of fracture, infection, or oncological disease. Three cohorts were created based on smoking status: non-smokers, former smokers, and current smokers. Outcome scores (American Shoulder and Elbow Surgeons (ASES), Constant-Murley score, Shoulder Pain and Disability Index (SPADI), Simple Shoulder Test (SST), University of California, Los Angeles activity scale (UCLA)), range of motion (external rotation (ER), forward elevation (FE), internal rotation, abduction), and shoulder strength (ER, FE) evaluated at two- to four-year follow-up were compared between cohorts. Evaluation of revision-free survival was performed using the Kaplan-Meier method to final follow-up.ResultsWe included 428 primary aTSAs with a mean follow-up of 2.4 years (SD 0.6). Our cohort consisted of 251 non-smokers, 138 former smokers who quit a mean 21 years (SD 14) prior to surgery (25 pack-years (SD 22)), and 39 current smokers (23 pack-years (SD 20)). At two- to four-year follow-up, former smokers had less favourable SPADI, SST, and FE strength compared to non-smokers, and current smokers had less favourable SPADI, SST, ASES score, UCLA score, Constant-Murley score, FE, abduction, and ER strength compared to non-smokers. Non-smokers exhibited higher revision-free survival rates at two, five, eight, and ten years postoperatively compared to former smokers and current smokers, who had similar rates.ConclusionOur study suggests that smoking has a negative effect on aTSA functional outcomes that may persist even after quitting.Cite this article: Bone Joint J 2024;106-B(11):1263–1272.